JP2014211632A - Manufacturing method of toner particles - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method with which a toner can be obtained which can be fixed at low energy, has sufficient heat-resistant storage stability, and suppresses a change in performance after storage at a high temperature.SOLUTION: There is provided a manufacturing method of toner particles containing a binder resin having a styrene-acrylic resin as a main component, a colorant, and a block polymer having a polyester portion and a vinyl polymer portion, the manufacturing method including a step of, after preparing resin particles by a suspension polymerization method or a dissolution suspension method and while having the resin particles dispersed in an aqueous medium, holding the temperature of the aqueous medium within a temperature range between a glass transition point TgA (°C) of the resin particles or higher and an onset temperature TmA (°C) of an endothermic peak due to the block polymer in the resin particles or lower for 60 minutes or longer at a temperature fluctuation range of 20°C or less and a temperature fluctuation rate of 0.35°C/min. or less.

Description

  The present invention relates to a method for producing toner particles used for forming a toner image by developing an electrostatic latent image formed by a method such as electrophotography, electrostatic recording, or toner jet recording.

In recent years, low power consumption has been demanded in printers and copiers, and improvement in toner performance has been demanded. On the other hand, it is demanded that the toner can be used without problems even in various environments, and it is simultaneously required that the heat-resistant storage stability of the toner is improved and the performance does not change due to storage.
In order to satisfy these requirements, it is necessary to eliminate the trade-off relationship of suppressing the change in physical properties during high-temperature storage while softening the toner.
To solve this problem, a toner to which a crystalline resin excellent in response speed to heat is added has been studied. However, simply adding a crystalline resin may not only deteriorate the heat-resistant storage stability of the toner, but also changes the crystallinity of the crystalline resin due to high-temperature storage, resulting in a deterioration in toner performance. There is a case. For this reason, toners that have been devised in various ways to utilize the characteristics of the crystalline resin have been proposed. Specifically, by placing the crystalline resin at a temperature below the melting point of the crystalline resin for a long time, the crystal of the crystalline resin grows, the heat resistant storage stability is improved, and the degree of crystallinity by standing at high temperature is increased. The device which suppresses change is made.
Patent Document 1 proposes a toner manufacturing method including a step of storing a toner containing a crystalline resin at a temperature of 45 ° C. or higher and 65 ° C. or lower. However, in the above-described toner manufacturing method, a part of the toner may aggregate due to the storage process at the temperature. In addition, by performing this process in a dry process, there is a possibility that the crystalline resin existing in the vicinity of the toner surface may move to the toner surface as the crystal grows, and the image density and other toner development performance may be reduced. was there.
Patent Document 2 proposes a toner in which a crystalline polyester is added to an amorphous polyester and heat-treated at a specific temperature below the melting point of the crystalline polyester. In the toner described above, since amorphous polyester is used for the binder resin, the crystalline polyester is compatible with the binder resin in the toner manufacturing process. Therefore, not only the efficiency of improving the degree of crystallinity in the subsequent heat treatment becomes very low, but also some components remain compatible, and sufficient heat-resistant storage stability may not be obtained. .
Patent Document 3 proposes a toner manufacturing method including a step of maintaining a suspension polymerization toner containing a crystalline resin at a temperature lower than the melting point of the crystalline resin in the manufacturing process. In the toner described above, the binder resin and the crystalline resin are incompatible. For this reason, the dispersion state of the crystalline resin in the toner is difficult to be uniform, and there are cases where sufficient low-temperature fixability and heat-resistant storage stability cannot be achieved even if the crystallinity is improved from that state.
As described above, in the toner introduced with the crystalline resin, various measures have been made to suppress the adverse effect on the storage stability while making full use of the fixing performance due to the addition of the crystalline resin, but sufficient performance can be obtained efficiently. No toner production method has been proposed yet.

JP 2006-065015 A JP 2009-128652 A JP 2012-002833 A

  The present invention provides a toner manufacturing method that solves the above-described conventional problems. That is, the present invention provides a production method capable of obtaining a toner that can be fixed with low energy, has sufficient heat-resistant storage stability, and has little change in performance due to storage at high temperatures.

The present invention
The following method i) or ii):
i) A polymerizable monomer, a colorant, and a polymerizable monomer composition containing a block polymer are added to an aqueous medium, granulated, and the polymerizable monomer contained in the granulated particles. To produce resin particles,
ii) A resin solution is prepared by dissolving or dispersing a binder resin, a colorant and a block polymer in an organic solvent, and the resin solution is added to an aqueous medium, granulated, and contained in the granulated particles. Removing the organic solvent to produce resin particles,
(A) to obtain resin particles by, and
A step (B) of maintaining the temperature of the aqueous medium for 60 minutes or longer so as to satisfy the following conditions in a state where the resin particles are dispersed in the aqueous medium;
I) A temperature not lower than the glass transition point TgA (° C.) of the resin particles and not higher than the onset temperature TmA (° C.) of the endothermic peak derived from the block polymer in the resin particles.
II) The temperature fluctuation range is 20 ° C. or less.
III) The temperature fluctuation rate is 0.35 ° C./min or less,
A method for producing toner particles comprising:
The toner particles are
a) a binder resin mainly composed of a styrene acrylic resin;
b) a colorant, and
c) containing a block polymer;
The block polymer is
a) having a polyester moiety and a vinyl polymer moiety;
b) having an endothermic peak,
The present invention relates to a method for producing toner particles.

  According to the present invention, it is possible to provide a production method capable of obtaining a toner that can be fixed with low energy, has sufficient heat-resistant storage stability, and has little change in performance due to high-temperature storage.

The figure which showed typically the domain structure formation of the block polymer by the annealing process in this invention The figure which showed the change of the endothermic characteristic before and after the annealing process in the conventional example The figure which showed the change of the endothermic characteristic before and behind annealing process in this invention Diagram showing domain structure formation of block polymer by annealing process in the conventional example The figure explaining system A of the annealing process in the present invention The figure explaining system B of the annealing process in the present invention The figure explaining the system C of the annealing process in the present invention The figure explaining the system D of the annealing process in the present invention The figure explaining the system E of the annealing process in the present invention

The inventors of the present invention have intensively studied the process of improving the crystallinity of the crystalline resin (hereinafter also referred to as an annealing process) by reviewing the molecular design of the crystalline resin and the binder resin. As a result, in the case of using a block resin having a vinyl polymer part and a polyester part as a crystalline resin having an endothermic peak in a binder resin having a styrene acrylic resin as a main component and measurement with a differential scanning calorimeter, A unique phenomenon was observed, and it was found that the effect of the annealing process was dramatically improved.
In the toner manufacturing method of the present invention, the following step (B) is an annealing step.
Step (B):
A step of maintaining the temperature of the aqueous medium for 60 minutes or more so as to satisfy the following conditions in a state where the resin particles are dispersed in the aqueous medium.
(I) A temperature not lower than the glass transition point TgA (° C.) of the resin particles and not higher than the onset temperature TmA (° C.) of the endothermic peak derived from the block polymer in the resin particles.
(II) The temperature fluctuation range is 20 ° C. or less.
(III) The temperature fluctuation rate is 0.35 ° C./min or less.

FIG. 2 shows a change in endothermic characteristics before and after the annealing process when a styrene acrylic binder resin and crystalline polyester are used as a conventional combination. The endothermic amount at the endothermic peak derived from the crystalline polyester is slightly increased, indicating that the crystallinity of the crystalline resin is improved.
On the other hand, the endothermic characteristics before and after the annealing step when using the binder resin in the present invention and a block polymer having a vinyl polymer part and a polyester part as a crystalline resin having an endothermic peak in measurement with a differential scanning calorimeter The change is shown in FIG. An endothermic peak is newly generated at a temperature different from the endothermic peak derived from the crystalline resin, and further, the annealing process continues to be fused with the original endothermic peak derived from the crystalline resin. It became very big. Therefore, in the present invention, when a block resin having a vinyl polymer portion and a polyester portion having an endothermic peak in measurement with a binder resin and a differential scanning calorimeter is used, a phenomenon different from the conventional one is caused. It is considered that the effect of the annealing process is greatly improved.
Although this phenomenon has not been clarified, it is considered that the existence state of the crystalline resin in the toner is caused. A case where crystalline polyester is used as the crystalline resin will be described as an example. In this case, the crystalline polyester is often present in the toner in the form of a domain that is completely phase separated from the binder resin as shown in FIG. However, some crystalline polyesters are compatible with the binder resin and lower the glass transition temperature of the binder resin. This can be confirmed from the analysis of the measurement data of the glass transition temperature of the toner. In general, when an annealing process is performed, it is presumed that crystal growth mainly occurs around the crystalline resin domain that originally exists. The component compatible with the binder resin is presumed to be crystallized by being integrated into the domain that originally exists, and it is considered that it takes a very long time to crystallize the component compatible with the binder resin.
On the other hand, when a block polymer having a vinyl polymer part and a polyester part is used as a crystalline resin having an endothermic peak in measurement with a differential scanning calorimeter, the crystalline resin is finely dispersed in the binder resin. The condition is often observed. As shown in FIG. 1, this is considered to be caused by the formation of a micelle-like finely dispersed state in which a polyester part is surrounded by a vinyl polymer part (reference polymer blend by Saburo Akiyama, CMC Publishing, December 1981). Issue 1st printing p172).
At this time, it is presumed that the components compatible with the binder resin are also in a micelle form. When the annealing process is performed from this state, crystal nuclei are quickly formed starting from the formed micelles, and this nucleation process causes a temperature different from the endothermic peak of the original crystalline resin. It is thought that an endothermic peak occurs in
Further, since the crystal nucleus grows by continuing the annealing process, the endothermic peak rises to a temperature equivalent to that of the original crystalline resin. In this step, it is considered that the crystal growth efficiency is drastically improved by the formation of crystal nuclei, and as a result, it is considered that the endothermic amount is greatly increased as described above.
As described above, the present inventors use a binder resin mainly composed of a styrene acrylic resin and a block polymer having a vinyl polymer part and a polyester part, which has an endothermic peak in measurement with a differential scanning calorimeter. In the toner particles, a unique phenomenon in the annealing process was found and the present invention was achieved.
As a general definition of block polymer, a polymer composed of a plurality of linearly connected blocks (the terminology of basic terms in polymer science by the Polymer Nomenclature Committee of International Union of Applied Chemistry of Polymers) The present invention follows the definition.
Here, “having a styrene acrylic resin as a main component” means that 50% by mass or more of the binder resin is a styrene acrylic resin. In the present invention, other binder resins used for conventionally known toners can be used within the range not impairing the effects of the present invention.

The block polymer of the present invention has a polyester site and a vinyl polymer site, and has an endothermic peak in measurement with a differential scanning calorimeter. In addition, although either the polyester site | part and vinyl polymer site | part which comprise a block polymer may be a crystalline site | part, from a soluble viewpoint with respect to binder resin, a polyester site | part is a crystalline site | part, and a vinyl polymer site | part. Is preferably an amorphous part.
In the vinyl polymer portion, for example, a known vinyl monomer such as styrene, methacrylic acid ester (for example, methyl methacrylate), and acrylic acid ester (for example, n-butyl acrylate) can be used as a constituent unit of the vinyl polymer portion. . It is more preferable to use styrene as the main structural unit of the vinyl polymer from the viewpoint of compatibility with a binder resin containing styrene acrylic resin as a main component and formation of a phase separation structure.

In the present invention, after the resin particles are produced by the suspension polymerization method or the dissolution suspension method as described above, the temperature of the aqueous medium is changed to the glass transition point TgA of the resin particles while the resin particles are dispersed in the aqueous medium. (° C) or more, within the temperature range of the endothermic peak derived from the block polymer in the resin particles, the onset temperature TmA (° C) or less, the temperature fluctuation range is 20 ° C or less, the temperature fluctuation rate is 0.35 ° C / min, This is achieved by holding for 60 minutes or more.
Here, the judgment as to whether or not the production of the resin particles has been completed is performed based on the polymerization conversion rate (% by mass) or the solvent removal rate (% by mass) of the resin particles. In the present invention, when the polymerization conversion rate or the solvent removal rate reaches 99.0% or more, it is considered that the production of the resin particles is completed, and the annealing step can be performed using the resin particles.
By producing the resin particles by the suspension polymerization method or the dissolution suspension method, it is possible to form a state in which the block polymer is dispersed in a micelle form in the binder resin. As a result, the effects of the present invention as described above can be obtained.
In addition, since the temperature of the aqueous medium in the annealing process is TgA (° C.) or higher and TmA (° C.) or lower, the molecular motion of the block polymer is not easily bound to the binder resin, and recrystallization of the block polymer occurs. The effect of the annealing process can be obtained.
Since the temperature fluctuation rate of the aqueous medium in the annealing process is 0.35 ° C./min or less, the crystal nuclei of the block polymer are efficiently formed, and the crystal growth is efficiently performed while finely dispersing the domain of the block polymer. It can be carried out.
Moreover, the heat resistance improvement effect accompanying crystallization of a block polymer is acquired because holding time is 60 minutes or more. Note that the upper limit of the holding time is not particularly defined, but even if the holding time is 1200 minutes or longer, the effect does not change greatly. Therefore, it may be determined based on the balance with the manufacturing efficiency.
Further, since the temperature fluctuation range of the aqueous medium in the annealing process is 20 ° C. or less, the formation of crystal nuclei of the block polymer and the crystal growth are performed at a sufficient rate, so that the block polymer is finely dispersed and has a high crystallinity. It can be in the state of.
The above-mentioned control enables compatibility between excellent low-temperature fixability (fixing at low energy) and heat-resistant storage stability, and enables the production of toner with little change in fixing performance and development performance even after high-temperature storage. It becomes.
In addition, about the said holding time, the total time of an annealing process should just be in the said range, and an annealing process may be performed in several steps. The holding time is preferably 120 minutes or longer. However, when the annealing process is performed in several steps, it is necessary to control the temperature of the aqueous medium in which the resin particles are dispersed not to be higher than TmA (° C.) during the annealing process.
Further, the temperature fluctuation rate may be changed during the annealing step as long as it is 0.35 ° C./min or less. The temperature fluctuation rate is preferably 0.20 ° C./min or less. Here, the temperature fluctuation rate is indicated by the maximum value of the value obtained by dividing the temperature fluctuation amount (° C.) of the aqueous medium in the annealing process by the time (minutes) required for the temperature fluctuation. In the present invention, when temperature fluctuations occur during the annealing process a plurality of times, it is only necessary that the temperature fluctuation speed calculated for each temperature fluctuation satisfies the above range. The temperature fluctuation rate is calculated based on the temperature change over a period of 5 minutes or more. Furthermore, the temperature fluctuation range in the entire annealing process is the difference between the maximum temperature and the minimum temperature of the aqueous medium during the annealing process, and is preferably 15 ° C. or less. In the present invention, when temperature fluctuations occur during the annealing process a plurality of times, it is only necessary that the temperature fluctuation width satisfies the above range in each temperature fluctuation.

  In the annealing step in the present invention, the temperature of the aqueous medium is equal to or higher than the glass transition point TgA (° C.) of the resin particles while the resin particles are dispersed in the aqueous medium, and the temperature at which heat generation due to the cold crystallization of the block polymer ends. It is preferable to be within a temperature range of TcA (° C.) or less. By being TcA (° C.) or lower, the crystal growth rate of the block polymer can be further increased, and low melting point components such as low molecular weight components can be sufficiently crystallized, so that the effect of annealing is further improved. growing. Thereby, more excellent heat resistance and developability can be obtained. About this TgA (degreeC), TmA (degreeC), and TcA (degreeC), it can control by the kind and molecular weight of the monomer which comprise each resin. In addition, the measuring method of this TgA (degreeC), TmA (degreeC), and TcA (degreeC) is mentioned later.

In the present invention, the composition of the polyester site constituting the block polymer is not particularly limited. However, as described above, the polyester part is preferably a crystalline part having an endothermic peak.
From the viewpoint of compatibility between low-temperature fixability and heat resistance and annealing efficiency, the polyester portion of the block polymer is composed of a dicarboxylic acid represented by the following formula (1) and a diol represented by the following formula (2). It is preferably a crystalline part.
HOOC- _{(CH 2)} m -COOH (1)
[Wherein m represents an integer of 6 to 14]
HO— (CH ₂ ) _n —OH Formula (2)
[Wherein n represents an integer of 6 to 16]
By using the above components, the dispersion of the block polymer in the toner particles can be made finer and the crystal growth rate during annealing becomes faster. Thereby, more excellent low-temperature fixability can be obtained while maintaining heat resistance.
A more preferable range of m is 7 to 10, and a more preferable range of n is 6 to 12.
Further, the solubility parameter (SP) value of the polyester part is more preferably 9.40 or more and 9.85 or less. By satisfying the above range, the compatibility between the binder resin and the block polymer at the time of melting becomes high, and a larger low-temperature fixing effect can be obtained.

In the present invention, the vinyl polymer part of the block polymer is an amorphous part, and its glass transition point TgB (° C.) is preferably TmA (° C.) or more. When the TgB (° C.) is equal to or higher than TmA (° C.), the annealing step is performed below the glass transition point TgB (° C.) of the vinyl polymer portion. Thereby, the crystallinity can be improved while suppressing the movement and rearrangement of the domain of the block polymer finely dispersed in the resin particles by the vinyl polymer part. As a result, it is possible to obtain better heat-resistant storage stability while maintaining low-temperature fixability.
The TgB (° C.) of the vinyl polymer moiety can be controlled by the type of monomer constituting the vinyl polymer moiety and the molecular weight of the vinyl polymer moiety.
Furthermore, it is preferable that the mass ratio of the polyester site | part and vinyl polymer site | part in this block polymer is 30: 70-70: 30, and it is more preferable that it is 40: 60-70: 30. By being in the above-mentioned range, it is possible to achieve both melting characteristics as a crystalline resin while finely dispersing the dispersion state of the block polymer in the resin particles. As a result, the effect in the annealing process can be obtained more efficiently while maintaining better low-temperature fixability. The ratio of the polyester part to the vinyl polymer part in the block polymer can be controlled by the production conditions such as the temperature and the synthesis time during production of the block polymer, the monomer charge ratio, and the like. In addition, the analysis method of the ratio of the polyester site | part and vinyl polymer site | part in this block polymer is mentioned later.

The temperature Tmp (° C.) at the apex of the endothermic peak of the block polymer is preferably 55 ° C. or higher and 100 ° C. or lower. When Tmp (° C.) of the block polymer is in the above range, it is possible to suppress a decrease in heat resistance while exhibiting low-temperature fixability due to addition of the block polymer. Tmp (° C.) is more preferably 60 ° C. or higher and 90 ° C. or lower.
The endothermic amount of the block polymer is preferably 20 J / g or more and 120 J / g or less, from the viewpoint of maintaining crystallinity when incorporated in toner particles and the crystal growth rate in the annealing step. More preferably, it is 90 J / g or less. By being in the above range, there is a portion that maintains the crystallinity even when it is contained in the toner particles, so that crystal growth is rapidly performed starting from this portion during the annealing step.
The Tmp (° C.) and the endothermic amount can be controlled by the type and molecular weight of the monomer constituting the polyester moiety in the block polymer. A method for measuring Tmp (° C.) and the endothermic amount will be described later.
The block polymer preferably has a weight average molecular weight (Mw) of 20,000 or more and 45,000 or less. When Mw is 20000 or more, the block polymer compatible with the binder resin is recrystallized more quickly in the annealing step. Moreover, when Mw is 45000 or less, the melt viscosity of the block polymer can be made suitable for low-temperature fixability. The weight average molecular weight (Mw) of the block polymer is more preferably 23,000 or more and 40,000 or less. The weight average molecular weight (Mw) of the block polymer can be controlled by the synthesis temperature and synthesis time during the production of the block polymer. In addition, the measuring method of the weight average molecular weight (Mw) of this block polymer is mentioned later.
In the present invention, the block polymer is prepared by preparing a polyester part and a vinyl polymer part separately, combining them, preparing a polyester part, and a vinyl monomer as a raw material for the vinyl polymer part. And a method of performing a polymerization reaction can be used.
In the present invention, the content of the block polymer is preferably 10 parts by mass or more and 100 parts by mass or less, and more preferably 10 parts by mass or more and 70 parts by mass or less with respect to 100 parts by mass of the binder resin.

Next, the method for producing toner particles of the present invention will be specifically described with reference to procedures and materials that can be used, but the present invention is not limited thereto.
The toner particles of the present invention are produced by producing resin particles using a suspension polymerization method or a dissolution suspension method, and then subjecting the resin particles to an annealing process in an aqueous medium.
First, a specific method for producing resin particles using the suspension polymerization method will be described.
Add a polymerizable monomer, a colorant and a block polymer to form a binder resin for toner particles, and use a disperser such as a homogenizer, ball mill, colloid mill, or ultrasonic disperser to add another monomer to the polymerizable monomer. A polymerizable monomer composition in which the components are melted, dissolved or dispersed is prepared. At this time, in the polymerizable monomer composition, if necessary, a release agent, a polar resin, a polyfunctional monomer, a pigment dispersant, a charge control agent, a solvent for adjusting viscosity, and the like. Additives (for example, chain transfer agents) can be added as appropriate.
Next, the polymerizable monomer composition is added to an aqueous medium containing a dispersion stabilizer prepared in advance, and granulated using a high-speed disperser such as a high-speed stirrer or an ultrasonic disperser. .
The polymerization initiator may be mixed with other additives when preparing the polymerizable monomer composition, or may be mixed into the polymerizable monomer composition just before being suspended in the aqueous medium. Good. Moreover, it can also be added in the state melt | dissolved in the polymerizable monomer and other solvent as needed during granulation or after completion of granulation, ie, just before starting a polymerization reaction.
Particles obtained by granulating particles by heating the suspension while stirring so that the particles of the polymerizable monomer composition in the suspension maintain the particle state and the particles do not float or settle. The polymerizable monomer contained therein is polymerized. Polymerization is completed, and an aqueous medium dispersion of resin particles is formed by performing residual polymerizable monomer removal treatment or solvent removal treatment as necessary.
Next, a specific method for producing resin particles using the dissolution suspension method will be described.
A binder resin, a colorant, and a block polymer are added to an organic solvent, and a resin solution is prepared by uniformly dissolving or dispersing them using a disperser such as a homogenizer, a ball mill, a colloid mill, or an ultrasonic disperser. At this time, a wax, a charge control agent, and an additive such as a dispersant can be appropriately added to the resin solution as necessary.
Next, the resin solution is added to a preliminarily prepared aqueous medium containing a dispersion stabilizer, and droplets of the dissolved resin are granulated using a high-speed disperser such as a high-speed stirrer or an ultrasonic disperser. To do.
In order to remove the organic solvent from the granulated particles, the entire system is gradually heated, and the organic solvent in the dissolved resin droplets is removed by evaporation. The organic solvent is removed from the dissolved resin droplets as described above to form an aqueous medium dispersion of resin particles.
The aqueous medium dispersion containing the resin particles formed in the above-described method is subjected to an annealing step according to the above-described conditions. The annealing step may be performed in the process of cooling the aqueous dispersion of resin particles, or may be performed by reheating after the aqueous dispersion of resin particles is once cooled. At this time, if necessary, a dispersion stabilizer such as a surfactant or inorganic fine particles may be added. Thereafter, the toner particles can be obtained by washing as necessary and drying and classifying by various methods.

As the polymerizable monomer constituting the styrene acrylic resin that is the main component of the binder resin, a vinyl polymerizable monomer capable of radical polymerization can be used. As the vinyl polymerizable monomer, a monofunctional polymerizable monomer or a polyfunctional polymerizable monomer can be used.
Monofunctional polymerizable monomers include styrene, α-methyl styrene, β-methyl styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, 2,4-dimethyl styrene, pn-butyl. Styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy styrene, and , Styrene derivatives such as p-phenylstyrene;
Methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate Acrylic polymerizable monomers such as n-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl acrylate, dibutyl phosphate ethyl acrylate, and 2-benzoyloxyethyl acrylate;
Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate Methacrylic polymerizable monomers such as n-nonyl methacrylate, diethyl phosphate ethyl methacrylate, and dibutyl phosphate ethyl methacrylate;
As polyfunctional polymerizable monomers, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol Diacrylate, polypropylene glycol diacrylate, 2,2'-bis (4- (acryloxydiethoxy) phenyl) propane, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene Glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol di Methacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2′-bis (4- (methacryloxydiethoxy) phenyl) propane, Examples include 2,2'-bis (4- (methacryloxypolyethoxy) phenyl) propane, trimethylolpropane trimethacrylate, tetramethylolmethane tetramethacrylate, divinylbenzene, divinylnaphthalene, and divinyl ether.
The above-mentioned monofunctional polymerizable monomer alone or in combination of two or more kinds, or a combination of a monofunctional polymerizable monomer and a polyfunctional polymerizable monomer, or multifunctional A polymerizable monomer can be used alone or in combination of two or more.
The SP value of the styrene acrylic resin is preferably 9.45 or more and 9.90 or less, more preferably 9.50 or more and 9.85 or less. By being in this range, it becomes easy to balance the phase separation state at the time of toner and the compatibility state at the time of melting, annealing can be performed more effectively, and a toner having better low-temperature fixability can be obtained. it can.

In the present invention, the toner particles contain a colorant. Known colorants such as various conventionally known dyes and pigments can be used as the colorant.
As the black colorant, carbon black, a magnetic material, or a color toned to black using yellow, magenta, and cyan colorants shown below can be used. As the colorant for cyan toner, magenta toner, and yellow toner, for example, the following colorants can be used.
As the yellow colorant, compounds represented by monoazo compounds, disazo compounds, condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complex methine compounds, and allylamide compounds are used as pigments. Specifically, C.I. I. Pigment yellow 74, 93, 95, 109, 111, 128, 155, 174, 180, 185.
As the magenta colorant, monoazo compounds, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds are used. Specifically, C.I. I. Pigment Red 2, 3, 5, 6, 7, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 144, 146, 150, 166, 169, 177, 184, 185, 202, 206, 220, 221, 238, 254, 269, C.I. I. Pigment Bio Red 19 and the like can be exemplified.
As the cyan colorant, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, and basic dye lake compounds can be used. Specifically, C.I. I. Pigment blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66.
These colorants can be used alone or in combination, and further in the form of a solid solution. When the following magnetic material is used as the black colorant, the amount added is preferably 40 parts by mass or more and 150 parts by mass or less with respect to 100 parts by mass of the binder resin. When carbon black is used as the black colorant, the amount added is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the binder resin. In the case of color toner use, it is selected from the viewpoints of hue angle, saturation, lightness, weather resistance, OHP transparency, and dispersibility in toner particles, and its preferred addition amount is based on 100 parts by mass of the binder resin. 1 parts by mass or more and 20 parts by mass or less.

  In the present invention, when toner particles are desired to be magnetic toner particles, the toner particles may contain a magnetic material. In this case, the magnetic material can also serve as a colorant. In the present invention, examples of the magnetic material include iron oxides such as magnetite, hematite, and ferrite; metals such as iron, cobalt, and nickel. Or alloys of these metals with metals such as aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium and mixtures thereof. .

  In the present invention, the release agent that can be used as needed is not particularly limited, and known ones can be used. For example, the following compounds are mentioned. Aliphatic hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, paraffin wax, Fischer-Tropsch wax; oxides of aliphatic hydrocarbon waxes such as oxidized polyethylene wax or block copolymers thereof; Waxes mainly composed of fatty acid esters such as waxes, sazol waxes, ester waxes, and montanic acid ester waxes; those obtained by partially or fully deoxidizing fatty acid esters such as deoxidized carnauba wax; aliphatic hydrocarbon waxes Waxes grafted with vinyl monomers such as styrene and acrylic acid; partially esterified products of fatty acids and polyhydric alcohols such as behenic acid monoglyceride; obtained by hydrogenation of vegetable oils and the like And methyl ester compounds having a Dorokishiru group.

In the present invention, the toner particles may contain a charge control agent. Among them, it is preferable to use a charge control agent that controls the toner particles to be negatively charged. Examples of the charge control agent include the following.
Organometallic compound, chelate compound, monoazo metal compound, acetylacetone metal compound, urea derivative, metal-containing salicylic acid compound, metal-containing naphthoic acid compound, quaternary ammonium salt, calixarene, silicon compound, nonmetal carboxylic acid compound and derivatives thereof Is mentioned. A sulfonic acid resin having a sulfonic acid group, a sulfonic acid group, or a sulfonic acid ester group can also be preferably used.
As the dispersion stabilizer added to the aqueous medium, known surfactants, organic dispersants, and inorganic dispersants can be used. Among these, inorganic dispersants can be suitably used because they are less likely to produce ultrafine toner particles, are less likely to lose stability with the polymerization temperature and the passage of time, are easy to wash and do not adversely affect the toner. . The following are mentioned as an inorganic dispersing agent. Polyvalent metal phosphates such as tricalcium phosphate, magnesium phosphate, aluminum phosphate and zinc phosphate; carbonates such as calcium carbonate and magnesium carbonate; inorganic salts such as calcium metasuccinate, calcium sulfate and barium sulfate; Inorganic oxides such as calcium hydroxide, magnesium hydroxide, aluminum hydroxide, silica, bentonite and alumina. These inorganic dispersants can be almost completely removed by adding an acid or an alkali after the polymerization and dissolving.

Below, the measuring method of each physical property value prescribed | regulated by this invention is described.
<Method for Measuring TgA, TmA, TcA, Tmp, TgB, and Glass Transition Point of Toner Particle>
The glass transition points of TgA, TmA, TcA, Tmp, TgB and toner particles are measured according to ASTM D3418-82 using a differential scanning calorimeter “Q1000” (TA Instruments).
The temperature correction of the device detection unit uses the melting points of indium and zinc, and the correction of heat uses the heat of fusion of indium.
Specifically, 2 mg of a measurement sample is precisely weighed, placed in an aluminum pan, an empty aluminum pan is used as a reference, and a temperature increase rate of 1 ° C./120° C. is measured between 0 ° C. and 120 ° C. Modulation measurement is performed at a setting of min and amplitude temperature range ± 0.318 ° C./min. In this temperature rising process, a specific heat change is obtained in the temperature range of 0 ° C to 120 ° C.
The glass transition point TgA (° C.) of the resin particles and the glass transition point of the toner particles are equidistant in the vertical axis direction from the extended straight line of each baseline before and after the specific heat change of the reversible specific heat change curve. The temperature at the point where the straight line in Fig. 2 and the curve of the step-like change part of the glass transition intersect.
The onset temperature TmA (° C) of the endothermic peak derived from the block polymer in the resin particle is a straight line obtained by extending the low temperature side base line to the high temperature side, and the endothermic peak at the point where the gradient is maximum on the low temperature side in the endothermic peak curve. The temperature at the intersection with the tangent line drawn on the curve. Further, the temperature at the top of the endothermic peak is Tmp (° C.), and the endothermic amount (J / g) is the endothermic amount derived from the block polymer. The endothermic amount is obtained by calculation from the endothermic peak area using analysis software attached to the apparatus.
On the other hand, Tmp of toner particles is measured in the same manner except that the measurement sample is changed to toner particles, and the temperature at the top of the endothermic peak is defined as Tmp (° C.). Further, the endothermic amount (J / g) is obtained from the endothermic peak area by calculation using analysis software attached to the apparatus.
In measuring the endothermic property of the vinyl polymer portion of the block polymer, the measurement is performed by hydrolyzing the polyester portion of the block polymer. Specifically, 5 ml of dioxane and 1 ml of a 10% by mass aqueous potassium hydroxide solution are added to 30 mg of the block polymer, and the polyester part is hydrolyzed by shaking at a temperature of 70 ° C. for 6 hours. Thereafter, the solution is dried, and the obtained solid content is dispersed and dissolved in ethanol. Furthermore, a vinyl polymer site | part is obtained by removing a melt | dissolution by filtration and washing | cleaning. Subsequent operations are performed in the same manner as the measurement for other resin components.
The temperature TcA (° C.) at which the heat generation due to the cold crystallization of the block polymer ends is the heat generated when the block polymer is measured at a measurement temperature of 100 ° C. to 0 ° C. at a temperature drop rate of 1 ° C./min. The temperature at the intersection of the straight line obtained by extending the base line on the low temperature side to the high temperature side at the peak and the tangent line drawn on the exothermic peak curve at the point where the gradient is maximized on the low temperature side in the exothermic peak curve.

<Measurement method of ratio of polyester part and vinyl polymer part of block polymer>
The ratio of the polyester part of the block polymer to the vinyl polymer part was determined by using nuclear magnetic resonance spectroscopy ( ¹ H-NMR) [400 MHz, CDCl ₃ , room temperature (25 ° C.)]. Measuring apparatus: FT NMR apparatus JNM-EX400 (manufactured by JEOL Ltd.)
Measurement frequency: 400MHz
Pulse condition: 5.0μs
Frequency range: 10500Hz
Number of integrations: The mass ratio (C / A ratio) between the polyester site and the vinyl polymer site was calculated from the integrated value of the spectrum obtained 64 times.

<SP value calculation method>
The SP value in the present invention was determined using the Fedors equation (1). Δei here,
And Δvi values refer to the evaporation energy and molar volume (25 ° C.) of atoms and atomic groups according to Tables 3 to 9 of the book “Basic Science of Coating”, pages 54 to 57, 1986 (Tsubaki Shoten).
δi = [Ev / V] ^1/2 = [Δei / Δvi] ^1/2 formula (1)
Ev: Evaporation energy V: Molar volume Δei: Evaporation energy of atom or atomic group of i component Δvi: Molar volume of atom or atomic group of i component For example, hexanediol is atomic group (—OH) × 2 + (— CH ₂ ) × 6, and the calculated SP value is obtained by the following equation.
δi = [Δei / Δvi] ^1/2 = [{(5220) × 2 + (1180) × 6} / {(13) × 2 + (16.1) × 6}] ^1/2
The SP value (δi) is 11.95.

<Method for measuring weight average molecular weight (Mw) of various resins>
The weight average molecular weight (Mw) of the block polymer or various resins is measured as follows using gel permeation chromatography (GPC).
First, a block polymer or various resins are dissolved in tetrahydrofuran (THF) at room temperature. Then, the obtained solution is filtered through a solvent-resistant membrane filter “Mysholy disk” (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the component soluble in THF is 0.8% by mass. Using this sample solution, measurement is performed under the following conditions.
Equipment: High-speed GPC equipment “HLC-8220GPC” [manufactured by Tosoh Corporation]
Column: Duplex of LF-604 [manufactured by Showa Denko KK]
Eluent: THF
Flow rate: 0.6 ml / min
Oven temperature: 40 ° C
Sample injection amount: 0.020 ml
In calculating the molecular weight of the sample, standard polystyrene resin (trade names “TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500 ", manufactured by Tosoh Corporation) are used.

<Measurement method of volume average particle diameter of fine particles>
The volume average particle size of the fine particles is measured using a Microtrac particle size distribution analyzer HRA (X-100) (manufactured by Nikkiso Co., Ltd.) with a particle size range of 0.001 to 10 μm, and the volume average particle size (μm or nm ) To measure.

<Method of measuring polymerization conversion rate or solvent removal rate of resin particles>
The polymerization conversion rate or solvent removal rate of the resin particles is measured as follows using gas chromatography (GC).
About 500 mg of resin particle dispersion is precisely weighed and placed in a sample bottle. About 10 g of acetone precisely weighed was added to the lid, mixed well, and mixed well. A desktop ultrasonic cleaner (trade name “B2510J-MTH”, manufactured by Branson) with an oscillation frequency of 42 kHz and an electrical output of 125 W was used. Irradiate with ultrasonic waves for 30 minutes. Thereafter, filtration is performed using a solvent-resistant membrane filter “Mysholy disk” (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm, and 2 μL of the filtrate is analyzed by gas chromatography. Then, the “residual amount” of the remaining polymerizable monomer or solvent is calculated by a calibration curve prepared using the polymerizable monomer or solvent used in advance. Thereafter, the polymerization conversion rate (% by mass) or the solvent removal rate (% by mass) of the resin particles is defined according to the following formula. (Formula) 100 × (1- (residual amount) / (total amount of polymerizable monomer or solvent used))

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. All parts used in the examples indicate parts by mass.

<Production of crystalline polyester 1>
While stirring by adding 100.0 parts of sebacic acid and 106.5 parts of 1,12-dodecanediol to a reaction vessel equipped with a stirrer, thermometer, nitrogen introduction tube, dehydration tube, and decompression device, the temperature is increased. Heated to 130 ° C. After adding 0.7 parts of titanium (IV) isopropoxide as an esterification catalyst, the temperature is raised to 160 ° C. and polycondensation is performed over 5 hours. Then, it heated up at the temperature of 180 degreeC, it was made to react until it became a desired molecular weight, making it reduce pressure, and polyester (1) was obtained. The weight average molecular weight (Mw) of the polyester (1) was 19000, and the melting point (Tm) was 84 ° C. The obtained polyester (1) is crystalline polyester 1.
<Manufacture of block polymer 1>
After adding 100.0 parts of polyester (1) and 440.0 parts of dehydrated chloroform to a reaction vessel equipped with a stirrer, a thermometer, and a nitrogen introducing tube and completely dissolving, add 5.0 parts of triethylamine. While cooling with ice, 15.0 parts of 2-bromoisobutyryl bromide was gradually added. Thereafter, the mixture was stirred at room temperature (25 ° C.) for a whole day and night to obtain a resin solution.
The resin solution was gradually dropped into a container containing 550.0 parts of methanol to reprecipitate the resin component, followed by filtration, purification and drying to obtain polyester (2).
Subsequently, 100.0 parts of the polyester (2) obtained above in a reaction vessel equipped with a stirrer, a thermometer, and a nitrogen introduction tube, 155.0 parts of styrene, 3.5 parts of copper (I) bromide, And 8.5 parts of pentamethyldiethylenetriamine was added and the polymerization reaction was performed at a temperature of 110 ° C. while stirring. When the desired molecular weight was reached, the reaction was stopped, and reprecipitation, filtration and purification were performed with 250.0 parts of methanol to remove unreacted styrene and catalyst. Then, it dried with the vacuum dryer set to 50 degreeC, and obtained the block polymer 1 which has a polyester site | part and a vinyl polymer site | part.

<Production of block polymers 2 to 11>
Block polymers 2 to 11 were obtained in the same manner as in the production method of the block polymer 1 except that the raw materials were changed as shown in Table 1.

尚、表中のｎ−ＢＡはｎ−ブチルアクリレートを意味する。

In the table, n-BA means n-butyl acrylate.

<Production of crystalline polyester 2>
While stirring by adding 100.0 parts of sebacic acid and 106.5 parts of 1,12-dodecanediol to a reaction vessel equipped with a stirrer, thermometer, nitrogen introduction tube, dehydration tube, and decompression device, the temperature is increased. Heated to 130 ° C. After adding 0.7 parts of titanium (IV) isopropoxide as an esterification catalyst, the temperature is raised to 160 ° C. and polycondensation is performed over 5 hours. Then the temperature 180 ° C
The crystalline polyester 2 was obtained by reacting to a desired molecular weight while reducing the pressure. The weight average molecular weight (Mw) of the crystalline polyester 2 was 35000, and melting | fusing point (Tm) was 84 degreeC.

  Table 2 shows the physical properties of the obtained block polymers 1 to 11 and crystalline polyesters 1 and 2.

<Production of resin particle dispersion 1>
Styrene 49.0 parts n-butyl acrylate 21.0 parts Pigment blue 15: 3 6.0 parts Aluminum salicylate compound 1.0 part (Bontron E-88 manufactured by Orient Chemical Co., Ltd.)
-Polar resin 5.0 parts (styrene-2-hydroxyethyl methacrylate-methacrylic acid-methyl methacrylate copolymer (mass ratio 95: 2: 2: 3), acid value = 10 mgKOH / g, glass transition point (Tg) = 80 ° C., weight average molecular weight (Mw) = 15000)
Release agent Paraffin wax 7.0 parts (HNP-9: manufactured by Nippon Seiki: melting point = 75 ° C.)
Block polymer 1 30.0 parts The above formulation was mixed, 15 mm ceramic beads were added thereto, and dispersed for 2 hours using an attritor (manufactured by Mitsui Miike Chemical) to obtain a polymerizable monomer composition. .
To a container equipped with a high-speed stirring device TK-homomixer (made by Tokushu Kika Kogyo Co., Ltd.), 800 parts of ion-exchanged water and 15.5 parts of tricalcium phosphate are added, and the number of revolutions is adjusted to 15000 revolutions / minute, 70 The mixture was heated to 0 ° C. to obtain an aqueous dispersion medium.
To the polymerizable monomer composition, 4.0 parts of t-butyl peroxypivalate as a polymerization initiator was added, and this was put into the aqueous dispersion medium. While maintaining 15000 revolutions / minute with the high-speed stirring device, the mixture was dispersed for 3 minutes for granulation (granulation step). Then, the stirrer is changed from the high-speed stirrer to the propeller stirring blade, the polymerization is performed for 8.0 hours while maintaining 70 ° C. while stirring at 150 rpm, and the temperature is raised to 100 ° C. and heated for 4 hours. Then, the solvent and the unreacted monomer were removed (polymerization step). The resin particle dispersion thus obtained is the resin particle dispersion 1.
A part of the dispersion was extracted, and the temperature was cooled to 20 ° C. while stirring was continued. It was 100.0 (mass%) when the polymerization conversion rate of the resin particle contained in the extracted dispersion liquid was measured. Resin particles 1 were obtained by washing and drying the extracted dispersion. The obtained resin particles had a TgA (° C.) of 45 ° C. and a TmA (° C.) of 75 ° C.

<Production of resin particle dispersions 2 to 13>
Resin particle dispersions 2 to 13 were obtained in the same manner as in the production method of the resin particle dispersion 1, except that the raw materials shown in Table 3 were changed.

<Production of resin particle dispersion 14>
The following materials were put in a reaction vessel equipped with a reflux condenser, a stirrer, and a nitrogen inlet tube under a nitrogen atmosphere.
・ Toluene 100.0 parts ・ Styrene 75.0 parts ・ n-butyl acrylate 25.0 parts ・ t-butyl peroxypivalate 3.0 parts The inside of the container was stirred at 200 rpm and heated to 70 ° C. And stirred for 10 hours. Further, the binder resin 1 was obtained by heating to 100 ° C. and distilling off the solvent for 6 hours. Then
-Binder resin 1 70.0 parts-Block polymer 1 30.0 parts-Release agent Paraffin wax 7.0 parts (HNP-9: Nippon Seiki melting point 75 ° C)
Pigment Blue 15: 3 6.0 parts Aluminum salicylate compound 1.0 part (Bontron E-88: manufactured by Orient Chemical Co., Ltd.)
-Ethyl acetate 200.0 parts The above components were mixed and dispersed in a ball mill for 10 hours, and the resulting dispersion was added to 2000 parts of ion-exchanged water containing 3.5% by mass of tricalcium phosphate, and a high-speed stirring device TK. -Granulation was performed with a homomixer at a rotational speed of 15000 rpm for 10 minutes. Thereafter, the mixture was held at 75 ° C. for 4 hours in a water bath while stirring at 150 rpm with a general-purpose stirrer (three-one motor), and the solvent was removed to obtain a resin particle dispersion 14.
A part of the dispersion was extracted, and the temperature was cooled to 20 ° C. while stirring was continued. It was 100.0 (mass%) when the solvent removal rate of the resin particle contained in the extracted dispersion liquid was measured. The extracted dispersion was washed and dried, and the obtained resin particles had a TgA (° C.) of 50 ° C. and a TmA (° C.) of 75 ° C.

<Production of resin particle dispersion 15>
(Preparation of binder resin dispersion)
-Styrene 75.0 parts-n-butyl acrylate 25.0 parts The mixture of the said prescription was disperse | distributed and emulsified in the aqueous medium, and was mixed slowly for 10 minutes. As an aqueous medium, 120.0 parts of ion-exchanged water, 1.5 parts of a nonionic surfactant (manufactured by Sanyo Chemical Co., Ltd .: Nonipol 400) and an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd.) ): Neogen SC) What dissolved 2.2 parts was used. While continuing to mix the emulsion, 10.0 parts of ion-exchanged water in which 1.5 parts of ammonium persulfate was dissolved as a polymerization initiator was added thereto. Further, after nitrogen substitution, the contents were heated with stirring until the temperature reached 70 ° C., and emulsion polymerization was continued for 4 hours. Thereafter, the amount of ion-exchanged water was adjusted so that the solid content concentration was 20.0% by mass to obtain a binder resin dispersion. The resin particles dispersed in the obtained binder resin dispersion had a volume average particle size of 0.29 μm.
(Preparation of block polymer dispersion)
-Block polymer 1 50.0 parts-Anionic surfactant 7.0 parts (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
-Ion-exchanged water 200.0 parts The above was heated to a temperature of 95 ° C and dispersed using a homogenizer (manufactured by IKA: Ultra Tarrax T50), and then dispersed with a pressure discharge type homogenizer. Thereafter, the amount of ion-exchanged water was adjusted so that the solid content concentration was 20.0% by mass to obtain a block polymer dispersion. The block polymer particles dispersed in the obtained block polymer dispersion had a volume average particle size of 0.31 μm.
(Preparation of colorant dispersion)
Cyan colorant (CI Pigment Blue 15: 3) 20.0 parts Anionic surfactant 3.0 parts (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
-Ion exchange water 78.0 parts The said prescription was mixed and it disperse | distributed using the sand grinder mill. Thereafter, the amount of ion-exchanged water was adjusted so that the solid content concentration was 20.0% by mass to obtain a colorant dispersion. When the particle size distribution in this colorant dispersion was measured using a particle size measuring device (LA-700, manufactured by Horiba, Ltd.), the volume average particle size of the colorant contained was 0.20 μm and 1.00 μm. No coarse particles exceeding were observed.
(Preparation of wax dispersion)
Hydrocarbon wax 50.0 parts (HNP-9: Nihon Seiki, melting point 75 ° C)
Anionic surfactant 7.0 parts (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
-Ion-exchanged water 200.0 parts The above formulation was heated to a temperature of 95 ° C and dispersed using a homogenizer (manufactured by IKA: Ultra Tarrax T50), and then dispersed with a pressure discharge homogenizer. Thereafter, the amount of ion-exchanged water was adjusted so that the solid content concentration was 20.0% by mass to obtain a wax dispersion. The wax particles dispersed in the obtained wax dispersion had a volume average particle size of 0.50 μm.
(Preparation of charge control particle dispersion)
-5.0 parts of metal compound of dialkyl salicylic acid (negative charge control agent, Bontron E-84, manufactured by Orient Chemical Industries)
-3.0 parts of anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
-78.0 parts or more of ion-exchanged water was mixed and dispersed using a sand grinder mill. Thereafter, the amount of ion-exchanged water was adjusted so that the solid content concentration was 5.0% by mass to obtain a charge control particle dispersion.
(Preparation of liquid mixture)
・ Binder resin dispersion 70.0 parts ・ Block polymer dispersion 30.0 parts ・ Colorant dispersion 6.0 parts ・ Wax dispersion 7.0 parts The above was equipped with a stirrer, cooling tube, and thermometer The mixture was put into a 1 liter separable flask and stirred. This mixed solution was adjusted to pH = 5.2 using 1 mol / L-potassium hydroxide.
To this mixed solution, 120.0 parts of a 8.0% by mass aqueous sodium chloride solution was added dropwise as a flocculant and heated to a temperature of 55 ° C. while stirring. At this temperature, 2.0 parts of a charge control particle dispersion was added. After maintaining at a temperature of 55 ° C. for 2 hours, observation with an optical microscope confirmed that aggregated particles having an average particle diameter of 3.3 μm were formed.
Then, after adding 3.0 parts of surfactant made from an anion (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC) here, it heated to 95 degreeC, continuing stirring, and hold | maintained for 4.5 hours. A part of the dispersion was extracted, and the temperature was cooled to 20 ° C. while stirring was continued. The extracted dispersion was washed and dried, and the obtained resin particles had a TgA (° C.) of 45 ° C. and a TmA (° C.) of 75 ° C.
Table 3 shows the physical properties of the obtained resin particle dispersions 1 to 15.

<Examples 1-39>
Using the resin particle dispersions 1 to 11 and 14, the annealing step was performed as shown in Table 4 and FIGS. 5 to 9, and then the temperature was cooled to 20 ° C. while stirring was continued. Thereafter, washing and drying were performed to obtain toner particles 1 to 39. Table 6 shows the physical properties of the toner particles 1 to 39 obtained.

<Comparative Examples 1-10>
Using resin particle dispersions 1, 12, 13, and 15, the annealing step was performed as shown in Table 5 and FIG. 5, and then the temperature was cooled to 20 ° C. while stirring was continued. Thereafter, washing and drying were performed to obtain toner particles 40 to 49.
The details of the methods A to E in the annealing step are as described with reference to FIGS.
First, each resin particle dispersion was heated to 100 ° C. at a rate of 0.5 ° C./min. Thereafter, for systems A to C, the temperature was cooled to 20 ° C. at a rate of 0.5 ° C./min, and further raised to the annealing start temperature at a rate of 1.0 ° C./min to start the annealing process. After the annealing process, the annealing process was cooled from the annealing process finish temperature to 20 ° C. at a rate of 0.5 ° C./min. In the method C, the process is divided into several times, but the cooling and heating process between the processes is cooled to 20 ° C. at a rate of 0.5 ° C./min, and annealing is started at a rate of 1.0 ° C./min. The temperature was raised to temperature.
For systems D and E, each resin fine particle was heated to 100 ° C. at a rate of 0.5 ° C./min, then cooled to the annealing start temperature at a rate of 1.0 ° C./min, and the annealing step was performed. Started. After the annealing process, the annealing process was cooled from the annealing process finish temperature to 20 ° C. at a rate of 0.5 ° C./min.
Further, when the annealing process was performed in a dry process (Comparative Example 10), a method was used in which the toner particles were spread in a metal bat with a thickness of about 1 cm and stored at a designated temperature. .
In addition, although all the above-mentioned annealing processes were performed using the water bath with respect to 1L of resin particle dispersion liquid, if the annealing process shown in this invention is performed, what may be used about a processing amount and a processing apparatus. Absent.
Table 6 shows the physical properties of the toner particles 40 to 49 obtained.

  When a plurality of endothermic peaks (toner particles) Tmp (° C.) shown in Table 6 were observed, a plurality of peak temperatures were indicated. The endothermic amount ΔH at that time is a total value including a plurality of endothermic peaks. When the endothermic peak derived from the block polymer overlaps with the endothermic peak derived from the release agent, the one obtained by subtracting the endothermic amount derived from the release agent was used. The endothermic amount derived from the release agent was calculated from the endothermic amount of the release agent alone and the charge amount of the release agent in the toner.

<Manufacture of each toner>
The toner particles obtained in Examples 1 to 39 and Comparative Examples 1 to 10 are classified, and then 100.0 parts of each toner particle is weighed, and silica fine particles 1 having a primary particle number average particle size of 40 nm are obtained. 0.0 part was added and mixed using a Henschel mixer (Mitsui Miike Chemical Co., Ltd.) to obtain each toner.

<Evaluation>
Each toner obtained was evaluated for performance according to the following method. Table 7 shows the evaluation results.
[Heat-resistant]
5 g of each toner was placed in a 50 mL polycup and allowed to stand for 3 days at a temperature of 50 ° C./humidity of 10% RH, and the presence or absence of aggregates was examined and evaluated.
(Evaluation criteria)
A: Agglomerates are not generated.
B: Minor agglomerates are generated and can be solved by light shaking.
C: A slight agglomerate is generated and can be released by lightly pushing with a finger.
D: Agglomerates are generated and do not collapse even when lightly pressed with a finger.
E: Completely aggregated.

[Developability]
(Development stripe)
A commercially available color laser printer (HP Color LaserJet 3525dn, manufactured by HP) was modified and evaluated so as to operate even when only one color process cartridge was installed. The toner contained in the cyan cartridge mounted on the color laser printer was extracted, the inside was cleaned by air blow, and the toner to be evaluated (300 g) was filled instead. Under normal temperature and humidity (23 ° C., 60% RH), a Canon office planner (64 g / m ² ) was used as an image receiving paper, and 500 sheets of a 2% printing rate chart were continuously drawn. After the image was printed, a halftone image was further output, and the presence or absence of image streaks in the halftone image and the presence or absence of streaks on the developing roller were observed, and developability was evaluated as follows.
(Evaluation criteria)
A: A vertical streak in the paper discharge direction, which appears as a development streak, is not seen on the developing roller or the halftone image.
B: Although there are 1 to 4 thin circumferential streaks at both ends of the developing roller, no vertical streak in the paper discharge direction, which appears as a developing streak, is seen on the halftone image.
C: There are 1 to 4 fine circumferential streaks at both ends of the developing roller, and several fine developing streaks can be seen on the image of the halftone portion.
D: There are five or more fine streaks in the circumferential direction at both ends of the developing roller, or five or more fine developing streaks are seen on the halftone image.
E: Many remarkable development streaks are observed on the developing roller and the image of the halftone portion.

(Reflection density)
Further, a solid image is output, and the solid image is compared with a printout image of a white background portion having a document density of 0.00 using a Macbeth densitometer (Macbeth Co., Ltd., using an SPI filter) which is a reflection densitometer. The reflection density was measured. The evaluation criteria are shown below. In addition, it means that it is excellent in developability, so that the value of reflection density is large.
(Evaluation criteria)
A: The reflection density is 1.40 or more.
B: The reflection density is 1.30 or more and less than 1.40.
C: The reflection density is 1.25 or more and less than 1.30.
D: The reflection density is 1.20 or more and less than 1.25.
E: The reflection density is less than 1.20.

[Aging characteristics]
Further, using the toner left for 30 days in an environment of a temperature of 45 ° C./humidity of 10% RH, the reflection density was measured, and the temporal change characteristic with respect to developability was evaluated. The evaluation criteria are shown below.
(Evaluation criteria)
A: The reflection density is 1.40 or more.
B: The reflection density is 1.30 or more and less than 1.40.
C: The reflection density is 1.25 or more and less than 1.30.
D: The reflection density is 1.20 or more and less than 1.25.
E: The reflection density is less than 1.20.

[Low temperature fixability]
A color laser printer (HP Color LaserJet 3525dn, manufactured by HP) with the fixing unit removed was prepared, and the toner was taken out from the cyan cartridge and filled with the toner to be evaluated instead. Next, an unfixed toner image (0.6 mg / cm ² ) having a length of 2.0 cm and a width of 15.0 cm is passed on the image-receiving paper (Canon office planner 64 g / m ² ) using the filled toner. It formed in the part of 1.0 cm from the upper end part with respect to the direction. Next, the removed fixing unit was remodeled so that the fixing temperature and the process speed could be adjusted, and a fixing test of an unfixed image was performed using this.
First, in a normal temperature and humidity environment (23 ° C., 60% RH), the process speed is set to 200 mm / s, the fixing linear pressure is set to 20.0 kgf, the initial temperature is set to 100 ° C., and the set temperature is gradually increased by 5 ° C. The unfixed image was fixed at each temperature.
Evaluation criteria for low-temperature fixability are as follows. The low temperature side fixing start point temperature is a lower limit temperature at which a low temperature offset phenomenon (a phenomenon in which a part of toner adheres to the fixing device) is not observed.
A: Low temperature side fixing start point temperature is 115 ° C. or lower.
B: Low temperature side fixing start point temperature is 120 ° C. or 125 ° C.
C: Low temperature side fixing start point temperature is 130 ° C or 135 ° C.
D: Low temperature side fixing start point temperature is 140 ° C. or 145 ° C.
E: The low-temperature side fixing start point temperature is 150 ° C. or higher.

Claims (5)

The following method i) or ii):
i) A polymerizable monomer, a colorant, and a polymerizable monomer composition containing a block polymer are added to an aqueous medium, granulated, and the polymerizable monomer contained in the granulated particles. To produce resin particles,
ii) A resin solution is prepared by dissolving or dispersing a binder resin, a colorant and a block polymer in an organic solvent, and the resin solution is added to an aqueous medium, granulated, and contained in the granulated particles. Removing the organic solvent to produce resin particles,
(A) to obtain resin particles by, and
A step (B) of maintaining the temperature of the aqueous medium for 60 minutes or longer so as to satisfy the following conditions in a state where the resin particles are dispersed in the aqueous medium;
I) A temperature not lower than the glass transition point TgA (° C.) of the resin particles and not higher than the onset temperature TmA (° C.) of the endothermic peak derived from the block polymer in the resin particles.
II) The temperature fluctuation range is 20 ° C. or less.
III) The temperature fluctuation rate is 0.35 ° C./min or less,
A method for producing toner particles comprising:
The toner particles are
a) a binder resin mainly composed of a styrene acrylic resin;
b) a colorant, and
c) containing a block polymer;
The block polymer is
a) having a polyester moiety and a vinyl polymer moiety;
b) having an endothermic peak,
And a method for producing toner particles.   The temperature of the aqueous medium in the step (B) is within a temperature range of not less than the glass transition point TgA (° C.) of the resin particles and not more than the temperature TcA (° C.) at which heat generation due to cold crystallization of the block polymer ends. The method for producing toner particles according to claim 1, wherein: 3. The toner particle according to claim 1, wherein the polyester portion of the block polymer is composed of a dicarboxylic acid represented by the following formula (1) and a diol represented by the following formula (2). Production method.
HOOC- _{(CH 2)} m -COOH (1)
[Wherein m represents an integer of 6 to 14]
HO— (CH ₂ ) _n —OH Formula (2)
[Wherein n represents an integer of 6 to 16]   4. The method for producing toner particles according to claim 1, wherein a glass transition point TgB (° C.) of a vinyl polymer portion of the block polymer is equal to or higher than TmA (° C.). 5.   The method for producing toner particles according to any one of claims 1 to 4, wherein a mass ratio of the polyester portion to the vinyl polymer portion in the block polymer is 30:70 to 70:30.

Images